1. Field of the Invention
This invention relates generally to digital communication systems and methods, and more particularly to a technique of channel encoding that deliberately inserts inter-symbol-interference (ISI) into the signal using a non-linear precoder to map data into a lattice that can have much better distance spectrum than an uncoded QAM signal, although it has nearly the same power level.
2. Description of the Prior Art
The channel coding problem is one of the key problems of the area of digital communications. There are numerous existing algebraic coding approaches directed to the channel coding problem, including block coding, lattice coding, trellis coding, convolutional coding and turbo coding, offering a tradeoff between robustness to channel's noise to power level, complexity and delay.